The current state of the art for coping with snow and ice on roads usually involves applying a deicer material such as a salt to the road surface. Sometimes antiskid materials such as sand or other aggregates such as gravel are added with or without a salt.
The use of salt and compositions having high concentrations of salt, cause an undesirable corrosive effect on vehicles, the road surface, and the environment with respect to the run off of water containing salt which contaminates the surrounding land and water.
Considering the above problems associated with salt formulations, there has been a continuing need for a deicing composition or formulation which can effectively melt snow and ice yet which reduces the corrosion and environmental contamination referred to above. In response to the above problems associated with the use of road salt, the prior art has looked to alternative formulations which are less corrosive and more environmentally friendly.
U.S. Pat. No. 5,635,101 (Janke et al.) relates to a deicing composition containing a by-product of a wet milling process of shelled corn. Corn kernels are steeped or soaked in a hot solution containing small amounts of sulfurous acid. The corn kernels are separated from the steep water and steep water solubles are used in the production of a deicing composition.
U.S. Pat. No. 4,676,918 (Toth et al.) relates to a deicing composition which comprises a mixture containing at least one component selected from a number of chlorides or urea and an admixture of waste concentrate of alcohol distilling that has a dry substance content of from 200 to 750 g/kg and from 10% to 80% by weight of water.
U.S. Pat. No. 6,080,330 (Bloomer) teaches a composition for use in preventing the formation of ice or snow on outdoor surfaces, such as roadways or aggregate stockpiles, and also for deicing surfaces upon which snow or ice has formed. The composition is formed from a waste product of the process of removing sugar from sugar beet molasses, also known as desugared sugar beet molasses.
The Janke et al., Toth et al. and Bloomer materials are naturally occurring substances with hundreds (if not thousands) of components such as complex carbo-hydrates, starches, sugars, proteins etc. and are normally used with a salt.
The above de-icing solutions now being introduced in the field employ agricultural residues e.g., corn based distillers solubles and solubles from the corn wet milling industries. These naturally occurring substances, which also include brewers condensed solubles, are extremely variable in composition, viscosity, film forming tendency, freezing temperature, pH etc., and consequently give varying performance when used in de-icing solutions. Depending upon the source and batch, these materials at low temperatures sometimes exhibit such resistance to flow that they cannot be applied evenly to a road surface or mixed with a chloride, rendering them virtually unsuitable for use.
Furthermore, these patents utilize materials which have highly undesirable or unnecessary ingredients leading to practical difficulties by manufacturers and users, such as stratification in storage, biological degradation, odor, plugging of filters and spray nozzles and environmental difficulties e.g. high biological oxygen demand due to the very high organic contents (about 40% by weight), presence of phosphorus compounds and heavy metals.
To improve quality and performance, and to meet current mandated standards, there is an immediate need for synthetic, chemically modified thickeners, and carefully purified materials which can be substituted for the currently used agricultural residues. Such a formulation would improve performance and reduce metal corrosion, spalling of concrete, toxicity and addresses environmental concerns.
It is therefore an object of the present invention to provide a deicing formulation which exhibits improved performance standards which overcomes the prior art problems described above.
It is a further object of the present invention to provide a deicing formulation which utilizes a synergistic combination of a low molecular weight carbohydrate and an inorganic freezing point depressant.
It is another object of the present invention to provide a deicing formulation which utilizes a low molecular weight carbohydrate to provide for improved ice melting properties and exhibits less corrosion.
It is a further object of the present invention to provide a deicing formulation which provides consistent physical and chemical properties, thereby assuring consistent quality and performance.
It is another object of the present invention to provide an economical, highly effective deicing formulation.